The use of radio frequency media for telephony became widely available in the last 15 years. The major application lies in areas where there is no substitute for the use of RF media, such as in mobile telephony.
However, even before mobile telephony became popular, there was a need for providing connectivity in the residential market. This need is much older than the use of the popular mobile telephony and presently exists along side the limited current use of radio frequency media for telephony.
More particularly, it has been many years since the typical consumer believed that a single telephone was sufficient. The perceived requirement for multiple telephones carried with it the need for connecting multiple telephones to the telephone network. The telephone network provides one or more telephone lines (or C.O. lines) to the location which is serviced, e.g. residences, businesses, etc. In order to support a telephone instrument, connectivity is required between the instrument and the termination of the C.O. line. In order to support multiple telephone instruments or other line type telephone devices, connectivity is required between each of the instruments or devices and the C.O. line termination. It is true that a small fraction of the need has been alleviated by the use of the "cordless" telephone. The "cordless" telephone consists of a base unit which must be hardwired to the telephone network and a "portable" hand-held unit. The "portable" hand-held unit is coupled to the base unit through RF media. However, the "cordless" telephone does not alleviate the major requirement for connectivity throughout a residence for several reasons. In the a first place, the residential user desiring multiple telephones cannot substitute the "cordless" telephone since there is only 1 "portable" handset per base unit. In addition, the quality of the RF link between the "portable" handset and the base unit is limited to voice application. Other applications which, today, are as important as voice include facsimile and modem traffic, neither of which can be accommodated on the RF link of a "cordless" telephone.
In general, the connectivity requirement can only be met by a system which is capable of handling a multiline application and which can be used to transmit/receive voice traffic, facsimile or modem traffic from any location in the residence. In other words, what is desirable is a wireless, in-house telephone system designed to provide multi-line phone operations, allowing the consumer to set up a multiple phone, multiple line system without having to use wired phone connections running throughout the building. Such a multi-line system allows any number of incoming phone lines to be routed to various phones, including wire line type phones, or phone-related devices, such as fax machines, modems, etc., regardless of where they are located, by using a wireless RF medium.